1. Field of the Invention
The present invention relates generally to a method and apparatus for remotely accessing, interacting and monitoring a computer system independent of the operating system, and more particularly to remotely displaying graphics-mode display data of the accessed computer system.
2. Description of Related Art
Advances in computing technology have caused a shift away from centralized mainframe computing to distributed computing using multiple personal computers (PCs) connected to a network. The network typically includes one or more server class personal computers to handle file, print and application services, which are common to all the connected PCs. Therefore, the server becomes an important resource which the entire network depends upon.
Oftentimes, businesses may require more than one server. Networks may demand isolation for security reasons. Networks may be logically subdivided for performance or practical reasons. In particular, networks may be in different geographic locations. However, oftentimes the maintenance and management of the servers falls onto a single group or person, called a network administrator. In these cases where the managed server is in an inconvenient location, it is desirable for the network administrator to be able to monitor the health of the managed server without traveling to its location.
In the past, the local network administrator operating from a remote management computer could telephonically connect into the operating system of a managed server to monitor its health using a conventional communications package such as PC Anywhere or ProComm. This method required a third communications computer to be attached to the network. Typically, a connection would first be established from the remote management computer to the communications computer attached to the network of the server. If the server was operating, the network administrator would be prompted for a login password to access network resources, including the server. If the server was down, only the communications computer could be accessed (providing that PC had its own modem). After the administrator logged into the network, a server console utility, such as RCONSOLE, could be executed to gain access to the server. Because many times the server would be down, this method had limited usefulness. Additionally, only limited information was provided, since the server would have to be operating before the server console utility would operate.
Network administrators also have used products such as Compaq's Insight Manager. This software product is loaded by the operating system to allow users to connect to the operating system through a dedicated modem using (remote access service) RAS/PPP (point to point) protocols. This method also allows insight into the operating system, but only after the server is operating.
To help in this regard, an accessory known as Compaq Server Manager R was developed. This accessory was essentially a personal computer system on an add-in board adapted to interact with the host server. Server manager R included a processor, memory, modem and software to operate independently of the server to which it was installed. To monitor the server from a remote location, the network administrator would dial into the server manager R board and establish a communications link. If a connection was established, the processor of server manager R would periodically acquire access to an expansion bus of the server to read the contents of the server video memory. The processor would then send the contents ***[text or graphics]*** to the local computer via the communications link. A separate power supply was provided to the server manager R board so that it would operate even while the server was booting or powered down. Although the functionality provided by the server manager R board was desired, because it was essentially a second computer, the high cost of this solution limited its success.
Later, a more integrated approach was taken with a device known as the integrated remote console (IRC) device. This device would connect to a conventional peripheral component interconnect (PCI) bus to monitor video activity. As PCI transactions were passed to a video controller also attached to the PCI bus, the IRC device would snoop the video transactions for the purpose of encoding the screen activity and sending the encoded data to a remote computer. IRC worked best with text-mode operating systems. If the server was running a graphical operating system, such as Microsoft Windows, the IRC device would cease to transmit information when the graphics mode was entered upon boot-up. Thus, although the IRC device was very useful for text-mode operating systems and to monitor graphical operating systems prior to entrance into graphics mode, a more complete solution was desired.